Aspects of the present disclosure relate generally to wireless communication networks, and more particularly, to space-time block coding (STBC) schemes for discrete Fourier transform spread orthogonal division multiplexing (DFT-s-OFDM or DFT-spread OFDM) in in new radio (NR) (also referred to as 5th generation (5G)) radio technologies.
Wireless communication networks are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include code-division multiple access (CDMA) systems, time-division multiple access (TDMA) systems, frequency-division multiple access (FDMA) systems, orthogonal frequency-division multiple access (OFDMA) systems, single-carrier frequency division multiple access (or multiplexing) (SC-FDMA) systems, and discrete Fourier transform spread orthogonal division multiplexing (DFT-s-OFDM) systems. It should be understood that SC-FDM and DFT-s-OFDM are two names of essentially similar technologies, however, DFT-s-OFDM is the terminology used in 3GPP specifications.
These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate on a municipal, national, regional, and even global level. For example, a fifth generation (5G) wireless communications technology (which can be referred to as new radio (NR)) is envisaged to expand and support diverse usage scenarios and applications with respect to current mobile network generations. In an aspect, 5G communications technology can include: enhanced mobile broadband addressing human-centric use cases for access to multimedia content, services and data; ultra-reliable-low latency communications (URLLC) with certain specifications for latency and reliability; and massive machine type communications, which can allow a very large number of connected devices and transmission of a relatively low volume of non-delay-sensitive information. As the demand for mobile broadband access continues to increase, however, further improvements in NR communications technology and beyond may be desired.
For example, for NR communications technology, the NR physical layer includes physical channels encoded and transmitted on a single OFDM symbol. Examples of such physical channels include PDCCH on the downlink (DL), and short-PUCCH on the uplink (UL), and PDSCH/PUSCH in a ‘mini-slot’ transmission (where a mini-slot is a 1-symbol slot). SC-FDM and/or DFT-s-OFDM versions of the same transmissions are also desirable, such as in UL link-budget limited case, and also in the DL for high carrier frequency (e.g., >40 GHz) transmissions. Also, a transmit diversity scheme may be desired for such transmissions.
Thus, improvements in wireless communications for NR technology and beyond may be desired.